Maternal obesity, diabetes linked to autism

Mothers who are obese or who have diabetes may be more likely to have children with neurodevelopmental disorders, including autism, research suggests.

Children whose mothers were obese were more likely to be diagnosed with an autism spectrum disorder (OR=1.67, 95% CI:1.10-2.56) or other developmental delay (OR=2.08; 95% CI:1.20-3.61) by age 5 years, Paula Krakowiak, MS, a PhD candidate at the MIND Institute at the University of California Davis, and colleagues reported in Pediatrics.

Krakowiak and colleagues enrolled 1,004 children aged 2 to 5 years in the Childhood Autism Risks from Genetics and the Environment (CHARGE) Study between January 2003 and June 2010, including 517 children with an ASD, 172 with a developmental delay and 315 controls with typical development.

Children were evaluated using the Mullen Scales of Early Learning (MSEL) and the Vineland Adaptive Behavior Scales (VABS) to assess cognitive and adaptive development. Mothers had three specific metabolic conditions assessed: obesity, hypertension and diabetes (type 2 or gestational) during pregnancy.

The researchers found that all three metabolic conditions occurred more frequently among the mothers of children with an ASD or other developmental delay. Combined rates for all conditions were 19.4% among mothers of typically developing children, versus 28.6% for mothers of children with an ASD and 34.9% for mothers of children with other developmental delays.

After adjusting for potential confounding factors, mothers with one of the three metabolic conditions were more likely to have a child diagnosed with an ASD (OR=1.61) or developmental delay (OR=2.35).

When the researchers looked at each metabolic condition separately, they found that maternal hypertension alone was not associated with either ASD or developmental delay. Maternal diabetes was associated with developmental delay (OR=2.33), but not ASD; whereas maternal obesity was associated with both conditions.

A “relatively small” association was observed between maternal diabetes and expressive language impairment among children with ASD, the researchers noted, and a wide rage of cognitive and adaptive developmental delays were observed among children without ASDs whose mothers had all three metabolic conditions.

The researchers emphasized that the study data are preliminary and do not prove cause and effect. Study limitations included the self-reported nature of medical conditions and the lack of data on glucose, insulin, lipid and immune biomarker measurements.